Method of texturing filament yarn



J y 4, 1967 G. A. JOHNSON METHOD OF TEXTURING FILAMENT YARN Filed Dec.26, 1963 FIG.2.

INVENTOR. GEORGE A. JOHNSON d n ATTORNEY United States Patent 3,329,757METHOD OF TEXTURING FILAMENT YARN George A. Johnson, Warrington, Fla.,assignor to Monsanto Company, a corporation of Delaware Filed Dec. 26,1963, Ser. No. 333,422 7 Claims. (Cl. 264--282) ABSTRACT OF THEDISCLOSURE v The tufting performance of continuous filament yarntextured by the hot-stretch gear-quench procedure is improved byforwarding the yarn before being stretched through a confined zone inwhich a stream of fluid moving at relatively low velocity is directedagainst the yarn. The fluid collides with the yarn therein to discomposethe parallelism of the yarn without inducing formation of loops orcompacting snarls therein.

The present invention relates to a method of texturing thermoplasticcontinuous filament yarn. More particularly, the present inventionrelates to such a method to render the yarn especially suitable for usein the production of tufted fabrics.

Today continuous filament man-made yarns are being used in textilefabrics requiring the yarn to have increased bulk, cover and likeproperties. The treating of such yarn to obtain the bulkincss is knownas texturing or lofting. In accordance with one texturing procedurewhich has enjoyed considerable commercial success in recent times,substantially untwisted thermoplastic continuous multifilament yarnshowing a low order of molecular orientation is hot stretched andimmediately thereafter is simultaneously cooled and deformed by beingpassed through a pair of cool meshing gear members. The resultingtextured yarn has the bulkiness needed in the construction of carpetsand upholstery fabrics, a significant part of which is produced today bythe use of tufting machines.

. It is recognized that the continuous filament yarn textured by thejust mentioned hot-stretch and gear-quench procedure exhibits a somewhatlower tufting performance than desired. In using such yarn on standardtufting machines, it is not uncommon for a single filament or a fewfilaments in the tufting operation to be diverted away from thethreadline bundle and to curl into the paths of the tufting needles. Thestray filaments are tagged or caught in an adjacent pile loop. Asstitching continues, the stray but strong filaments are extended alongthe backstitching until suflicient force is developed to pull one ormore pile loops out of the backing material. These pulled-out loops mustbe replaced or mended, a costly and undesirable operation; otherwise, avoid will be evident on the face of the tufted product. Normally, themending of tufted carpets is performed as the greige carpeting isinspected on a burling frame located in tandem with the tuftingmachines, the productivity of which is governed by the time required tomend. Mending results in down time for the tufting machines andobviously is undesirable.

It is an object of the present invention to provide a method oftexturing man-made thermoplastic continuous filament yarn.

"ice

the yarn is traveling, a stream of fluid moving at relatively lowvelocity is directed at an angle against the yarn. The fluid collideswith the yarn in a confined zone to discompose the parallelism of theyarn without inducing formation of loops or compacting snarls therein.Next, the parallelistically discomposed yarn is drawn at an elevatedtemperature to increase the molecular orientation thereof. Immediatelythereafter the drawn yarn is simultaneously deformed and cooled by beingpassed between relatively cool meshing gear members. The resultingtextured yarn is taken up in an orderly manner and has improved tuftingperformance as compared with yarn textured in the same way but withoutpre-discomposing the filaments.

The invention is illustrated in the accompanying draw- 7 ing wherein:

FIGURE 1 is a schematic view illustrating a continuous filament yarnbeing textured by the process of the present invention; and

FIGURE 2 is a schematic view of a fluid jet in cross section providing aconfined zone in which the filaments are brought into disorder.

In FIGURE 1 man-made thermoplastic continuous multi-filament yarn 1 hassubstantially no twist therein and has not been drawn. Nascent man-madefilaments as a rule, do not show a high order of molecular orientationand have a relatively low load-bearing capacity. The source of the yarnis provided in the form of a package 2 wound on a bobbin 3. Although theyarn is shown as having been packaged, the yarn can be supplied directlyfrom a filament-forming device without the yarn having been packagedprovided the yarn is substantally undrawn and twist-free.

The yarn is forwarded from the source by means of a thread advancingdevice, such as feed rolls 4, to supply it at a predetermined deliveryspeed to fluid jet 5. As shown, the jet is tubular and the yarn passestherethrough. It is important that correct tension be maintained on theyarn as it passes through the jet. For best results the tension shouldbe maintained uniformly low, preferably not exceeding 0.5 gram perdenier and usually above 0.01 gram per denier, the exact tensiondepending upon the type of discomposing fluid used, the mass velocity ofthe fluid and the yarn count (denier and number of filaments). All thesefactors are interrelatedly controlled to provide the required disturbingof the parallelism of the filaments without placing snarls of loopstherein.

Jets of somewhat similar construction have been used to place crunodalloops in drawn filaments. But, in the present process, the formation ofsuch loops is to be avoided, since their presence adversely interfereswith the subsequent drawing and deforming treatment of the pres- It is afurther object to provide an improved method of ent process. Jets ofsimilar construction have also been used to snarl or entangle thefilaments of yarn to compact same so that it has some characteristics ofhighly twisted yarn. Obviously, this snarling is to be avoided in thepresent process, since the objective herein is to provide a textured orlofted yarn with a coherent thread bundle. A highly twisted yarn or onehaving a simulated twist due to the presence of snarls cannot acquirethe desired bulky character of textured yarn.

In FIGURE 2, one form of jet 5 is shown on an enlarged scale in crosssection. Yarn 1 passes therethrough from the entry port 6 to the exitport 7. A fluid such as compressed air, steam, mist, etc., is flowedthrough side arm 8 of the jet. The jet of fluid collides with the yarnand deranges the threadline at 9 as seen in the drawing. The impingementof the fluid on the yarn at an angle discomposes same to disturb theparallelism of the filaments and to cause a moderate amount ofcriss-crossing of the filaments.

A source of supply of fluid is shown at 10 in FIGURE 1.

3 The fluid flows to the jet via line 11 at a controlled rate.Ordinarily, a mass velocity of 4 to 15 pounds per minute per square inchis quite suitable when compressed air is employed. (The mass velocity isbased upon the cross section of the inlet side arm of the jet.) In oneaspect of the present invention a measured amount of yarn finish orlubricant in the form of small particles suspended in and moved with airis brought into disturbing contact with the yarn in the jet. Thisaccomplishes the required discomposing of the filaments while at thesame time evenly distributing the yarn beneficiating agent throughoutthe yarn bundle.

From the feed rolls 4 the non-parallelized yarn 1 is led through zone Awherein the yarn is given a hot stretch. That is, the yarn is heated anddrawn to change the filaments thereof from their undrawn state to auniformly drawn, highly oriented state. Heated pin 12 provides thenecessary heat and at the same time localizes the point of draw.Obviously, other means of heating the yarn in zone A can be used.

The yarn is forwarded through the zone at the required speed by crimpinggears 13 driven by means 14 at a peripheral speed greater than thedelivery speed of feed rolls 4 to provide the required attenuation ofthe filaments. As the teeth of the gears mesh, the yarn is subjected tolaterally applied stresses increasing and decreasing in intensity as theyarn approaches and leaves the horizontal plane in which the axes of thecrimping gears lie. While subjected to the action of the gear teeth thehot drawn yarn is deformed at the same time it is cooled. To providethis cooling or quenching which is of importance to obtain the texture,gears 13 can be positively cooled. As illustrated nozzle 15 supplies thecoolant from source 16. Usually, it is advantageous to pass the yarnthrough the mesh of the gears a plurality of times, particularly wherethe total denier of filaments is high. To do this, a separator roll 17can be positioned adjacent to one of the gears.

After being cooled and deformed by the gears, the yarn is ordinarilytaken up in an orderly manner. As shown the yarn is wound in form of apackage 18 employing a conventional ring twister mechanism 19.

The invention can advantageously use as a starting material, undrawnfilament yarn prepared from a variety of polymers, including polyamides,polyesters, polyurethanes polyureas, polyacrylonitriles,polyhydrocarbons (polyethylene, polypropylene, etc.), polyvinylchlorides, cellulose esters and cellulose ethers, as well as many othermaterials. The yarn can have a round cross-section as well as anon-round cross-section such as X and Y configurations. In addition, theyarn can be tubular or have discontinuous voids. It is preferred thatthe yarn be made of polymeric ethylene terephthalate or of nylon whichis a class of polyamides. In particular nylon 6 (polymeric 6-aminocaproic acid) and nylon 66 (polyhexamethylene adipamide), as wellas various copolymers of nylon can be advantageously processed. Whenthese specific nylons are employed, best results are obtained bymaintaining the heating zone in the range of about 150250 C.

The following example is illustrative of the invention; but, the sameobviously is not limited thereto.

Example The filaments used as a yarn source were prepared by meltspinning nylon 66. The filament had a Y-shaped cross section. A yarnwith no twist and composed of 68 of these undrawn filaments, each ofwhich had a denier of about 60, was wound onto a bobbin from a spinningmachine. Apparatus of FIGURE 1 was used to treat the yarn except thatfluid jet was not part of the equipment. At a speed of 350 yards perminute the yarn was forwarded to the hot stretch zone A. The temperatureof pin 12 was 170 C. The yarn was fed between gears 13 driven so that astretch of 350 percent was accomplished. The yarn was passed through thegears for an additional two 4 times. Then, the yarn was packaged.Several packages were used to tuft a carpet using a conventional tuftingmachine. During tufting it was noted that errant filaments 'resulted inpulled-out tufts and in residual deformed tufts on the face side of thecarpeting. To mend the carpeting lowered the productivity of the tuftingmachine to about 30%.

Similarly spun yarn was treated in accordance with the presentinvention. The yarn under a tension of 0.05 gram per denier was passedthrough the jet 5 in which the diameter of the inlet arm was 0.0625. Airwith a mass velocity of 8 pounds of air per minute per square inch ofinlet jet cross section was directed at right angles to the yarn withinthe jet. (This rate is equivalent to an average linear air velocity ofabout 260 ft. per second.) The action of the air disturbed theparallelism of the filaments resulting in moderate cross-crossingthereof without formation of loops and snarls. The yarn washot-stretched and gear-quenched as above in this example. The yarn wasused to tuft a carpet. During tufting it was noted that only rarely diderrant filaments occur. Productivity of the tufting machine using thesefilaments increased to about This is a highly favorable improvement intufting productivity compared with the productivity when tufting yarnwhose filament parallelism was not disturbed in accordance with theinvention.

The process herein affords many advantages. Discomposed yarns texturedby the hot-stretch gear-crimp procedure have enhanced tuftingperformance. The process requires no complex apparatus and is quiteeconomical. In addition, the over-all properties of the texture o theyarn show significant improvement. 1

Discomposition of the parallelism of the yarn permits better heattransfer during drawing. More uniform texture and cohesion of threadbundle and more uniform distribution of residual finish is apparent.

It is evident that many different embodiments of the above can be madewithout departing from the spirit and scope of the present invention.Therefore, it is not intended that the invention be limited except asindicated in the following claims.

What I claim is:

1. A method of texturing man-made thermoplastic continuous multifilamentyarn comprising:

(a) forwarding substantially untwisted undrawn thermoplastic continuousfilament yarn longitudinally from a source of supply;

(b) directing a stream of fluid moving at a low velocity against theforwarded yarn in a confined zone to discompose the parallelism of theyarn such that same is substantially free of loops and compactingsnarls;

(c) drawing the discomposed yarn at an elevated temperature to increasethe molecular orientation thereof;

(d) simultaneously deforming and cooling the drawn yarn by passing samebetween cool toothed meshing gear members; and

(e) taking up the yarn in an orderly manner.

2. The method of claim 1 wherein the fluid is air moving at a massvelocity of about 4 to 15 pounds of air per minute per square inch ofcross section of the inlet to the jet.

3. The method of claim 1 wherein the yarn is made from a nylon polymer.

4. The method of claim 3 wherein the yarn is made from nylon 66.

5. The method of claim 3 wherein the yarn is made from nylon 6.

6. The method of claim 3 wherein the yarn is made from a co-polymernylon yarn.

7. The method of claim 1 wherein the yarn is made from a polymericethylene terephthalate.

(References on following page) 5 References Cited UNITED STATES PATENTS2,435,891 2/ 1948 Lodge. 2,869,967 1/ 1959 Breen. 3,110,151 11/1963Bunting et a1.

6 3,115,691 12/1963 Bunting et a1. 3,137,911 6/1964 Bromley 264-282 X3,238,590 3/1966 Nicita et a1.

5 ALEXANDER H. BRODMERKEL, Primary Examiner.

I. H. WOO, Assistant Examiner.

1. A METHOD OF TEXTURING MAN-MADE THERMOPLASTIC CONTINUOUS MULTIFILAMENT YARN COMPRISING: (A) FORWARDING SUBSTANTIALLY UNTWISTED UNDRAWN THERMOPLASTIC CONTINUOUS FILAMENT YARN LONGITUDINALLY FROM A SOURCE OF SUPPLY; (B) DIRECTING A STREAM OF FLUID MOVING AT LOW VELOCITY AGAINST THE FORWARDED YARN IN A CONFINED ZONE TO DISCOMPOSE THE PARALLELISM OF THE YARN SUCH THAT SAME IS SUBSTANTIALLY FREE OF LOOPS AND COMPACTING SNARLS; (C) DRAWING THE DISCOMPOSED YARN AT AN ELEVATED TEMPERATURE TO INCREASE THE MOLECULAR ORIENTATION THEREOF; (D) SIMULTANEOUSLY DEFORMING AND COOLING THE DRAWN YARN BY PASSING SAME BETWEEN COOL TOOTHED MESHING GEAR MEMBERS; AND (E) TAKING UP THE YARN IN AN ORDERLY MANNER. 